The absolute best-case scenario for the C's is if Orlando sucks, Dwight gets p---ed, makes it known that he's leaving and Orlando has to trade him. We'll have KG's contract to make the numbers work, but not much else.
LA has a lot more to offer Orlando in a trade... but what if Boston was willing to absorb Arenas/Turkoglu, as well? We aren't going to have young players to send back, but maybe we could clean off a lot of salary from Orlando's books.
That's how you're going to get Dwight - via trade at next years' deadline. You'd have to renounce your Bird rights to KG (and Ray) to have enough cap space to sign him in 2012, anyway.